User Manual

CELLTECH RESEARCH INC. Test Report S/N: 092601-169ARU
1955 Moss Court, Kelowna Date of Tests: October 16, 2001
B.C. Canada V1Y 9L3 FCC SAR Evaluation
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© 2001 Celltech Research Inc. RELM WIRELESS CORP. FCC ID: ARURPV516A 11
Portable VHF PTT Radio Transceiver (150-174MHz)
16.0 MEASUREMENT UNCERTAINTIES
Uncertainty Description Error Distribution Weight Standard
Deviation
Offset
Probe Uncertainty
Axial isotropy
±0.2 dB
U-Shaped 0.5
±2.4 %
Spherical isotropy
±0.4 dB
U-Shaped 0.5
±4.8 %
Isotropy from gradient
±0.5 dB
U-Shaped 0
±
Spatial resolution
±0.5 %
Normal 1
±0.5 %
Linearity error
±0.2 dB
Rectangle 1
±2.7 %
Calibration error
±3.3 %
Normal 1
±3.3 %
SAR Evaluation Uncertainty
Data acquisition error
±1 %
Rectangle 1
±0.6 %
ELF and RF disturbances
±0.25 %
Normal 1
±0.25 %
Conductivity assessment
±5 %
Rectangle 1
±5.8 %
Spatial Peak SAR Evaluation
Uncertainty
Extrapolated boundary effect
±3 %
Normal 1
±3 % ±5 %
Probe positioning error
±0.1 mm
Normal 1
±1 %
Integrated and cube orientation
±3 %
Normal 1
±3 %
Cube Shape inaccuracies
±2 %
Rectangle 1
±1.2 %
Device positioning
±6 %
Normal 1
±6 %
Combined Uncertainties
±11.7 % ±5 %
Measurement uncertainties in SAR measurements are difficult to quantify due to several
variables including biological, physiological, and environmental.
According to ANSI/IEEE C95.3, the overall uncertainties are difficult to assess and will vary
with the type of meter and usage situation. However, accuracy’s of ± 1 to 3 dB can be expected
in practice, with greater uncertainties in near-field situations and at higher frequencies (shorter
wavelengths), or areas where large reflecting objects are present. Under optimum measurement
conditions, SAR measurement uncertainties of at least ± 2dB can be expected.
According to CENELEC, typical worst-case uncertainty of field measurements is ± 5 dB.
For well-defined modulation characteristics the uncertainty can be reduced to ± 3 dB.